The ADC121S051 is a low-power, single channel CMOS 12-bit analog-to-digital converter with a high-speed serial interface. Unlike the conventional practice of specifying performance at a single sample rate only, the ADC121S051 is fully specified over a sample rate range of 200 ksps to 500 ksps. The converter is based upon a successive-approximation register architecture with an internal track-and-hold circuit.